1. Field of the Invention
The present invention relates generally to a system to increase the communication and sensing capabilities of a surface craft. More particularly, this invention relates to sensor and communications equipments carried in a balloon tethered to a surface craft to increase line-of-sight sensing and communication.
2. Description of the Prior Art
Line-of-sight (LOS) communications are being used to provide secure high-speed transfers of data to-support tactical operations. Currently, only satellites are capable of supporting LOS communications and transfer of data over the considerable distances where ships, aircraft, and submarines are typically separated during anti-submarine warfare (ASW) operations. However, satellite communications are expensive, limited by channel availability, require large antennas for two-way communications (found only on ships having large decks), and cannot always be as flexible as required to meet the changes that frequently, rapidly develop during ASW operations.
Aircraft that drop sonobuoys to listen for submarines must then orbit high in the sky to monitor them and receive their LOS data. The high orbiting of the aircraft prevents them from flying low where they are more likely to detect a submarine visually or though the use of radar, MAD, or FLIR which work better at low altitudes. Another factor to consider is that the number of aircraft and ships for ASW is decreasing so that each ship/aircraft is forced to cover larger areas of search. Consequently, they may miss some of the LOS data, and this potential constraint places additional stress on personnel to effectively coordinate and share the gathered data to find submarines that are becoming even quieter.
Currently, there is a limitation of the amount of improvement that can be obtained through improving the location or size of the antenna/sensor packages to increase detection/reception ranges. In addition, many antenna/sensor packages may have their capabilities restricted to one degree or another and may not be able to perform their functions effectively by being placed on a ship where LOS may be compromised by electromagnetic interference, and other competition from other on-board systems. Size, location, and weight of some antennas may affect the ship""s stability (roll), delectability, and the amount of power that may be available to a system without impacting other systems, and some active and passive countermeasures may interfere with the operation of other shipboard systems. Loading a ship with sensors and communications packages may actually create a further problem since hostile cruise missiles may home in on these packages. Since an effective defense against cruise missiles is to draw attacking cruise missiles away from a ship, it may be better to locate the packages the missiles home onto someplace else besides on the ship.
Thus, in accordance with this inventive concept, a need has been recognized in the state of the art for a system including a balloon towed behind a moving ship that supports appropriate instrumentation packages overhead to improve line-of-sight sensing and communication capabilities.
The first object of the invention is to provide an improvement for surface craft, or ships to improve their line-of-sight sensing and communication capabilities.
Another object of the invention is to provide a system including a balloon tethered to and towed by a ship to support sensors and/or communications equipment to improve their LOS (line-of-sight) capabilities.
Another object of the invention is to provide a towed airborne array system providing improved performance of sensor and communications equipments with ships, submarines, and aircraft operating in larger areas.
Another object of the invention is to provide a towed airborne array system improving the performance of existing sensors and communications equipments.
Another object of the invention is to provide a system for monitoring sonobuoys from a surface ship to free ASW aircraft from orbiting and monitoring duties.
Another object of the invention is to provide a system for monitoring sonobuoys from a surface ship and/or unmanned, autonomous buoys to free ASW aircraft from orbiting and monitoring duties.
Another object of the invention is to provide a towed airborne array system that increases flexibility to use power and transmission bands for communications.
Still another object of the invention is to provide a towed airborne array system that permits less reliance on satellites and provides twenty-four hour improved capabilities in line-of-sight communications and data sensing.
Another object of the invention is to provide a towed airborne array system that increases capabilities for mine detection and countermeasures performance.
These and other objects of the invention will become more readily apparent from the ensuing specification when taken in conjunction with the appended claims.
Accordingly, the present invention provides a towed airborne array system including a balloon towed behind a moving surface ship that supports appropriate instrumentation packages overhead to improve line-of-sight sensing and communications.